Immunohistochemical study of renal fibropoiesis associated with dogs naturally and experimentally infected with two different strains ofLeishmania(L.)infantum

Abstract

Summary The objectives of this work were to study some pathological aspects of kidneys obtained from dogs naturally infected with Leishmania infantum and from dogs experimentally infected with two different strains of L infantum with special emphasis on fibrotic process. Seventy eight specimens of paraffin‐embedded kidney fragments were collected as follows: (a) CNI group composed by 62 kidney samples of adult mongrel dogs, naturally infected with L infantum; (b) BH401 group composed by five kidney samples of adult Beagles experimentally infected with L infantum strain MCAN BR/2002/BH401; (c) BH400 group composed by eleven kidney samples of adult Beagles experimentally infected with L infantum strain MCAN/BR/2000/BH400, at the same dose and same route of the previous group, denominated group BH400; Control group (CC) composed by four kidney samples of adult Beagles. All animals revealed glomerular and interstitial fibropoiesis associated with different types of glomerulonephritis and chronic interstitial nephritis. Fibrosis was markedly more intense in the BH401 group, followed by animals in the CNI group. Markers for myofibroblasts (mesenchymal markers) such as alpha‐actin (α‐SMA), vimentin and the cytokine transforming growth factor beta (TGF‐β) were done by immunohistochemistry. BH401 group showed higher expression of all these markers than others. Intracellular amastigotes forms of Leishmania was mainly found in BH401. These results could be indicating that the MCAN/BR/2002/BH401 strain is a good choice for the study of renal LVC experimental model.

Role of the IL-33/ST2 Activation Pathway in the Development of the Hepatic Fibrosis Induced by Schistosoma mansoni Granulomas in Mice

“…The liver sections were stained with haematoxylin-eosin to evaluate the overall inflammation and tissue damage. Masson’s trichrome and Picrosirius red staining were performed to illustrate extracellular collagen deposition around parasite eggs, and Gomori’s ammoniacal silver staining to characterise the reticular fibre organisation [ 89 , 90 , 91 , 92 ]. Moreover, picrosirius-stained slides were examined under polarised light microscopy (Opticam, O500R, São Paulo, Brazil) to characterise collagen composition; type I collagen appears as red fibres, and type III collagen appears as green fibres under polarised light [ 89 ].…”

Canine Visceral Leishmaniasis: A Histological and Immunohistochemical Study of Fibropoiesis in Chronic Interstitial Pneumonitis

“…of promastigotes forms of L. infantum strain MHOM/BR/1972/BH46. Both parasite strains were inoculated at the end of the logarithmic growth phase after culture in α-MEM culture medium (GIBCO BRL) supplemented with 10% inactivated fetal calf serum (Sigma-Aldrish, Darmstadt, Germany), 200 U penicillin/L (Sigma), and 100 µg/mL streptomycin (Sigma), pH 7.4, at 24-26 • C [13].…”

“…All dogs were tested monthly after infection for the presence of Leishmania antibodies by indirect immunofluorescence and ELISA [12]. L. infantum infection was also confirmed by real-time polymerase chain reaction (RT-PCR) in samples of tissues, such as livers, spleens, or cervical lymph nodes, as previously described [13,14].…”

“…Using a digital pad, the total area occupied by stained collagen fibers was measured from real images and segmented to generate binary images. The results are expressed in square micrometers (Kontron Elektronic/Carl Zeiss, Germany) [4][5][6][7][8][9][10][11][12][13][14].…”

Pathomechanisms in the Kidneys in Selected Protozoan Parasitic Infections

“…But at 90 dpi, the TGF-β level was significantly higher than at 60 dpi. Using the immunohistochemistry method, expression of TGF-β was also detected in the kidneys of dogs infected with L. infantum [ 40 ]. Higher expression was noted in the kidneys of dogs infected with the parasite compared with the control group.…”